Method and apparatus for high-speed inkjet printing

Abstract

Image data for printing an image on a printable medium at high speed with an inkjet printer is received in memory in the form of 512 pixels, or a multiple thereof, wide with a resolution of 360 dots per inch, and saved as an 8 bit color TIFF file with no compression and thereafter stripped into multiple printing columns, one for each color, the columns being positioned in a printing flow order with a spacing between columns of 512 pixels, or a multiple thereof, and then this stripped image data is saved as a four bit bitmap file. The printing medium objects are sequentially conveyed under the printheads whereby the stripped image data is printed onto the printing medium by the inkjet nozzle columns to generate the image. UV ink is employed, together with a UV curing light source to provide high-speed curing.

1 . A method for processing image data for printing on a printable medium, comprising the steps of:
 receiving the image data in the form of 512 pixels, or a multiple thereof, wide at a resolution of 360 dots per inch;   saving the image data as an 8 bit color TIFF file with no compression;   stripping the saved image data into multiple printing columns, one for each color, and positioning the columns in a printing flow order with a spacing between columns of 512 pixels, or a multiple thereof; and   saving this stripped image data as a 4 bit BMP file.   
   
   
       2 . The method of  claim 1 , wherein there are four of said colors, namely, black, yellow, magenta and cyan. 
   
   
       3 . The method of  claim 2 , wherein the printing flow order of said columns is black, yellow, magenta and cyan. 
   
   
       4 . The method of  claim 1 , wherein said image data includes an image length of up to 18 inches. 
   
   
       5 . The method of  claim 1 , wherein levels of gray for said image data are received and converted from 256 levels to 4 levels, with levels 0-64 saved with a value of 0, levels 65-128 saved with a value of 1, levels of 129-192 saved with a value of 2, and levels of 193-256 saved with a value of 4. 
   
   
       6 . The method of  claim 1 , including halftoning the stripped image. 
   
   
       7 . A printing apparatus for printing an image represented by image data onto printable medium, comprising;
 a plurality of printheads, each having an elongated array of ink jetting nozzles; one array for each color, said arrays positioned in parallel with each other with a spacing of 512 pixels, or a multiple thereof;   a processor programmed for receiving the image data in the form of 512 pixels, or a multiple thereof, wide at a resolution of 360 dots per inch and saving the data in memory as an 8 bit color TIFF file with no compression, and for stripping the saved image data into multiple printing columns, one for each color, and positioning the columns in a printing flow order with a spacing between columns of 512 pixels, or a multiple thereof, and saving this stripped image data in memory as a 4 bit BMP file;   said processor associated with each printhead for distributing the stripped image data to respective of said printheads;   whereby the stripped image data may be printed onto the printable medium to generate the image to be printed.   
   
   
       8 . The printing apparatus of  claim 7 , wherein said printheads are stationary and multiples of the printable medium are sequentially conveyed in one direction under said printheads for printing an image thereon. 
   
   
       9 . The printing apparatus of  claim 8 , wherein the direction of elongation of said arrays is transverse to said one direction of conveyance. 
   
   
       10 . The printing apparatus of  claim 9 , wherein there are four of said colors, namely, black, yellow, magenta and cyan. 
   
   
       11 . The printing apparatus of  claim 10 , wherein said printing flow order from front to back along the one direction of conveyance is black, yellow, magenta and cyan. 
   
   
       12 . The printing apparatus of  claim 7 , wherein ink used in said apparatus for printing is UV curable ink. 
   
   
       13 . The printing apparatus of  claim 7 , wherein ink used in said apparatus for printing includes the jetable fluids of primer or overcoat. 
   
   
       14 . The printing apparatus of  claim 7 , wherein levels of gray for said image data are received and converted from 256 levels to 4 levels, with levels 0-64 saved with a value of 0, levels 65-128 saved with a value of 1, levels of 129-192 saved with a value of 2, and levels of 193-256 saved with a value of 3. 
   
   
       15 . An inkjet printer comprising:
 a plurality of printheads, each having a column of inkjet nozzles, each column for respectively jetting a different color;   wherein an image is recorded on a printable medium by conveying the printable medium respectively under the inkjet nozzle columns which are arranged in parallel in a direction perpendicular to the medium conveyance direction;   said columns of inkjet nozzles being spaced at intervals of 512 pixels, or a multiple thereof, along the medium conveyance direction;   a processor programmed for receiving image data in the form of 512 pixels, or a multiple thereof, wide at a resolution 360 dots per inch and saving the data in memory as an 8 bit color TIFF file with no compression, and for stripping the saved image data into multiple printing columns, one for each color, and positioning the columns in a flowing order in the direction of printable medium conveyance with a spacing between columns of 512 pixels, or a multiple thereof, and saving this stripped image data in memory as a 4 bit BMP file; and   said processor associated with each printhead for distributing the stripped image data to respective of said printheads;   whereby the stripped image data may be printed onto the printable medium by said inkjet nozzle columns to generate the image to be printed.   
   
   
       16 . The inkjet printer of  claim 15 , wherein there are four of said colors, namely, black, yellow, magenta and cyan. 
   
   
       17 . The inkjet printer of  claim 16 , wherein said printing flow order from front to back along the direction of conveyance is black, yellow, magenta and cyan. 
   
   
       18 . The inkjet printer of  claim 15 , wherein ink used in said apparatus for printing is UV curable ink. 
   
   
       19 . The printing apparatus of  claim 15 , wherein ink used in said apparatus for printing includes the jetable fluids of primer or overcoat. 
   
   
       20 . The printing apparatus of  claim 15 , wherein levels of gray for said image data are received and converted from 256 levels to 4 levels, with levels 0-64 saved with a value of 0, levels 65-128 saved with a value of 1, levels of 129-192 saved with a value of 2, and levels of 193-256 saved with a value of 3.